Subject: Re: [stella] 1 cycle! From: Thomas Jentzsch <tjentzsch@xxxxxx> Date: Mon, 17 Mar 2003 22:49:16 +0100 |
Fabrizio wrote: > So, any idea on saving up cycles in that function is welcome.. I'm willing > to use Illegal/Undocumented opcodes too, if required! No illegal opcodes this time. :-) You should move the code after BCS DrawBall2 behind JMP X3. This will save you one cycle in the timing critical path. For saving more cycles you could merge BallEnableTab and BallShiftTab, because HMBL and ENABLE can share the bits. With some shifting you can feed CTRLPF too (but that will cost 2 extra cycles): lda BallTab,y ; hhhhsse0 sta HMBL sta ENABL asl asl ora #5 ; hhsse101 sta CTRLPF Have fun! Thomas _______________________________________________________ Thomas Jentzsch | *** Every bit is sacred ! *** tjentzsch at web dot de | ---------------------------------------------------------------------------------------------- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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